JavaScript/TypeScript Implementation of Ascon

This is a JavaScript/TypeScript (JS compiled from TypeScript) implementation of Ascon v1.3, an authenticated cipher and hash function. It allows to encrypt and decrypt any kind of message. Includes the authenticated encryption and hash function variants as specified in NIST SP 800-232 (initial public draft). Heavily inspired by the python implementation of Ascon by https://github.com/meichlseder/pyascon

Notice: This library does contain the version 1.3 of Ascon. v1.2 was a draft version and there are already newer versions of ascon. See https://github.com/ascon/ascon-c . Version 1.2 is not compatible with 1.3

About Ascon

Ascon is a family of authenticated encryption (AEAD) and hashing algorithms designed to be lightweight and easy to implement, even with added countermeasures against side-channel attacks. It was designed by a team of cryptographers from Graz University of Technology, Infineon Technologies, and Radboud University: Christoph Dobraunig, Maria Eichlseder, Florian Mendel, and Martin Schläffer.

Ascon has been selected as the standard for lightweight cryptography in the NIST Lightweight Cryptography competition (2019–2023) and as the primary choice for lightweight authenticated encryption in the final portfolio of the CAESAR competition (2014–2019).

Find more information, including the specification and more implementations here:

https://ascon.iaik.tugraz.at/

About me

I have made library for AES PHP/JS encryption already in the past. Bit juggling is somewhat cool, in a really nerdy way. I like the Ascon implementation and it at the time of writing, a JS implementation was missing. So i made one. Would be cool if you leave a follow or spend some virtual coffee.

PHP Implementation

Chances are high that you probably need a PHP implementation too. I've made one here -> https://github.com/brainfoolong/php-ascon

Installation

# for npm
npm install js-ascon
const JsAscon = require('js-ascon')
# in browser
<script src="ascon.js"></script>

Usage

For more demos see in folder demo.

// test convenient methods
let key = 'mypassword'
let message = ['this can be any data type 😎 文', 123]
let associatedData = 'Some data 😋 文 This data is not contained in the encrypt output. You must pass the same data to encrypt and decrypt in order to be able to decrypt the message.'
let encrypted = JsAscon.encryptToHex(key, message, associatedData)
let decrypted = JsAscon.decryptFromHex(key, encrypted, associatedData)
JsAscon.assertSame(JSON.stringify(message), JSON.stringify(decrypted), 'Encryption/Decryption to hex failed')

// raw usage of basic methods
// key must be 16 bytes or 20 bytes, depending on variant
const key = [0x90, 0x80, 0x70, 0x60, 0x50, 0x40, 0x30, 0x20, 0x10, 0xAA, 0x90, 0x90, 0x90, 0x90, 0xCC, 0xEF]
// nonce must be 16 bytes and should always be random bytes, you must use same nonce for encrypt and decrypt the same message
const nonce = JsAscon.getRandomUintArray(16)
// this is the text you want to encrypt
const plaintext = 'Hi, i am a secret message!'
// associated data is not being encrypted, but is taken into account in the ciphertext
// this means, you can only decrypt when you pass the exact same associated data to the decrypt function as well
// so you can make sure that associated data and plaintext is not manipulated for given encrypted message
// this is optional and can be an empty string
const associatedData = 'Some data to pass to encryption and decryption - This data is not contained in the ciphertext output.'
const ciphertextByteArray = JsAscon.encrypt(key, nonce, associatedData, plaintext)
const plaintextDecrypted = JsAscon.decrypt(key, nonce, associatedData, ciphertextByteArray)

console.log("Hash")
console.log(JsAscon.hash("Testmessage"))

console.log("Mac")
console.log(JsAscon.mac(key, "Testmessage"))

Development

Change code in src/ascon.ts. Test changes with npm run tests-bun or npm run tests-node. Create dist files with npm run dist.

Algorithms

This is a simple reference implementation of Ascon as specified in NIST's draft standard, NIST SP 800-232, which includes

• Authenticated encryption JsAscon.encrypt and JsAscon.decrypt

  • Ascon-AEAD128

• Hashing algorithms JsAscon.hash including 3 hash function variants with slightly different interfaces:

  • Ascon-Hash256 with fixed 256-bit output
  • Ascon-XOF128 with variable output lengths (specified with hashlength)
  • Ascon-CXOF128 with variable output lengths (hashlength) and supporting a customization string as an additional input (to be implemented)

• Message Authentication Code JsAscon.mac

  • Ascon-Mac (128-bit output, arbitrarily long input),
  • Ascon-Prf (arbitrarily long input and output),
  • Ascon-PrfShort (t-bit output for t<=128, m-bit input for m<=128)

Older Algorithm Variants

Older versions implement Ascon v1.2 as submitted to the NIST LWC competition and published in the Journal of Cryptology, as well as additional functionality for message authentication. These versions can be found in at https://github.com/brainfoolong/js-ascon/tree/d6a74535555078767fcfe5bd47e7f6376fdad93a, including

• Authenticated encryption:

  • Ascon-128
  • Ascon-128a
  • Ascon-80pq

• Hashing algorithms:

  • Ascon-Hash
  • Ascon-Hasha
  • Ascon-Xof
  • Ascon-Xofa

• Message authentication codes ascon_mac(key, message, variant="Ascon-Mac", taglength=16) for 5 MAC variants (from https://eprint.iacr.org/2021/1574, not part of the LWC proposal) with fixed 128-bit (Mac) or variable (Prf) output lengths, including a variant for short messages of up to 128 bits (PrfShort).

  • Ascon-Mac
  • Ascon-Maca
  • Ascon-Prf
  • Ascon-Prfa
  • Ascon-PrfShort